Tension control apparatus



March 24, 1942. I G. E. HENNING ET AL 2,277,102

` TENSION CONTROL APPARATUS l Filed Aug. 28, 1941.

/fv vE/vTo/as 6. E. HENN/NG J. A. WA GNER `ATTOHNEY Patented Mar. 24, 1942 l UNITED STATES y PATENT OFFICE 'rENsroN coN'rnoL APPARATUS George E. Henning, Joppa, and Julius A. Wagner, Baltimore, Md., asslgnors to Western Electric Company, Incorporated, New York, N. Y., a corporation of New York Application august 2s. 194i, semi No. 408,610

12 Claims.

This invention relates to tension control apparatus, and more particularly to apparatus for controlling the tension of a strand drawn from a supply reel in a strand twisting machine.

'Ihere are various types of strand twisting machines, the type of particular interest regarding this invention including rotary supports for supply reels to cause twisting of individual strands or groups' of strands withdrawn from each reel prior to their being twisted together to form a cable. To produce a satisfactorily uniform cable it is important to apply a constant known tension to the strands, that they may be given like individual twists and lmay lie evenly in the cable they help to form. In the application of tension to a strand, withdrawn from a reel rotated by the withdrawal of the strand and simultaneously revolved about an axis normal to the axis of the reel, there exists the added problem of eliminating the effect of centrifugal force on the tensioning means.

An object of the invention is to provide a simple, efiicient and highly practical tension con'- trol apparatus free of variations by centrifugal force.

With this and other objects in view, the invention comprises a tension control apparatus for a strand withdrawn from a supply reel rotatable about its axis by the withdrawal of the strand and revoluble about an axis normal to the axis of the reel, a brake on an axis at right angles to the reel axis under the control of the strand eifecting rotation of the reel during any variation in the tension oi the strand.

Other'objects and advantages will be apparent from the following detailed description when taken in conjunction with the accompanying drawing, wherein Fig. l is a side elevational view of a fragmentary portion of a strand twisting machine embodying the invention;

Fig. 2 is a top plan View ci the structure shown in Fig. l;

machine. The strand twisting machine may include a plurality of units, such as shown in Figs. 1 and 2, depending upon the number of strands to be singly twisted and subsequently intertwisted to form a cable. Further details of the machine are not believed essential to illustrate the invention, as the invention lies in the single unit illustrated in the drawing.

One end of the bracket l has a cone it adjustable axially by a screw i5 and otherwise rotatably mounted on a shaft portion i6 journalled in the end of the bracket and engaged by the screw. The cone It is formed to engage the hub the shaft 22 and has a cone-shaped portion 2d Fig. 3 is an enlarged horizontal sectional'view whose function is similar to that of the cone .it inentering the hub of the reel i8 to support the reel. A pin 25 fixed to the member 23 is positioned to enter an aperture 26 of the reel to provide a positive connection between the reel and 'the shaft 22.

A bevelled gear 28 is mounted upon the shaft Hand xed for rotation with the shaft. This gear is disposed in interengagement with a bevelled gear 2, the latter being fixed to the adjacent end oi a brake shaft 3i) which extends through a bearing iii in a wall of the hollow end of the bracket i@ and into another hollow portion iii? of the bracket through an aperture 33.- In actual construction the shaft 363 is in two parts, as illustrated in Fig. 3, 'these parts being joined by a telescoping connection indicated at 35.1'. Suitable covers it and t? are providedfor the hollow end of the bracket iii and a ksuitable cover 38 is provided for the hollow portion 32 of the bracket. i

Cover 38 is formed to provide a bearing d@ for the adjacent end of the shaft et. On this end of the shaft 3@ a plurality of brake elements d2 is mounted ior rotation with the shaft, these elements being disk-like in general contour and having a plurality of friction members t3 disposed in spaced apertures therein. The mounting of the brake elements on the shaft it is made through keys and keyways or spline connections (not shown) to permit 4axial movement of the switch elements relative to the shaft it, yet will maintain positive connection for rotation of the elements with the shaft. Brake members 4,5 are positioned alternately with the brake elements 42, as illustrated in Fig. 3, one brake member being disposed at each endl of the group of brake elements, the other brake members being interposed between the brake elements. Suitably for one end of a spring 49. The other end of the spring is supported by a tubular member 50 disposed in the hollow portion 32 adjacent the inner wall thereof and concentric with the shaft 30 During rotation of the reel I5 through the withdrawal of the strand I9, the shaft 22 is rotated, causing rotation of the shaft 30 through the gears 25 and 29, thus rotating the brake elements 42 relative to the brake members 45. The force of the spring 49 on the adjacent member 45 causes axial movement of the brake members and the brake elements into closer engagement with each other to create a braking force transmitted back to the reel through the shafts 39 and 22 and their driving connections to apply a tension on the strand I9. 1

Means is provided to. vary the force of the spring 49 by variations in the tension of the strand. to function in maintaining a substantially constant tension in the strand. This means includes a sheave'55 over which the strand travels while being withdrawn from the reel. The sheave 55 is rotatably mounted at 55 between arms 51 which are fixed at their lower ends to a U-shaped supportlSB. In the present structure the support 58A is circular in cross-sectional contour, the legs thereof lying substantially parallel to the legs of the bracket- I and extending between sets of supporting rolls 59. The sets of supporting rolls are identical with each other and are supported by shafts journalled in brackets integral with the legs of the bracket I0 (Figs. 1 and 2). As illustrated in Fig. 1, the lower rolls of the sets of supporting rolls 59 are cylindrical in contour, while the upper rolls thereof, as shown in Fig. 2, are concave to conform to the contour of the legs of the support 55 to maintain accurate positioning of the support during movement thereof.

A bracket 50 is xed to one leg of the support 58 at a position shown in Fig. 2, and by any suitable means (not shown). A spring I, having one end fixed to the bracket I5, functions to normally urge the support to the left to normally urge the sheave 55 away from the reel I5 to a given position. The other end of the spring 5I is xed to an adjusting pin 53 about which the spring is disposed, a threaded lug 54 integral with the bracket I0 receiving a threaded portion 55 of the pinforadjustment of the pin relative to the bracket 50 to vary the force of the spring 5I.

A lever 51, pivotally mounted at 55 (Figs. 1 and Y form of a pin carried by the adjacent arm of the bracket I0. Adjacent the pivot 55, but interscrew 14 is of a sufficient contour to be slidably disposed in the aperture 59 and to engage the adjacent end of the tubular member 50 associated with the spring 49. The other end of the screw 14 has a head 15 through the aid of which, assisted by a suitable tool, adjustment may be made between the screw 14 and the nut 13 to vary the normal force of the spring 49 on the brake members and brake elements and to vary lthe effect of the brake controlling means resulting from variations in the tension of the strand and including the support 55 and its operative connection with the screw 14. As shown in Fig. 4, the nurl 13 is split as at 15 so that it may be caused to grip the screw 14 and be locked thereon in any adjusted position through the aid of a screw 19. Adjustment of the nut 13 is another means in addition to the adjustment of the pin 63 to vary the setting of the braking force on the reel. The force in the spring 49 influencing the brake elements and members is initially controlled by the force in the spring 5I which is transmitted to the spring 49 through the connecting means of the two springs and influenced greatly by the lever 51.- The relation of the spring connections 1I) and 12 with the lever and the pivot 59 thereof renders the small spring 5I effective to control the force in the large spring 49.

During the operation of the machine the reel .I5 will be rotated about its' axis through the withdrawal of the strand I9 therefrom. During this action the reel is revolved about the axis of the shaft II, which is normal to the reel axis.` Rotation of the reel I5 through its connection 25-25 with the member 23 will cause rotation of the shaft 22 on its axis which is aligned with the axis of the reel. However, the shaft 30, through the gears 25 and 29, is driven on an axis at right angles to the axis of the reel. This causes relay tive rotation of the brake elements and brake members, affected by the force of the spring 49, to apply a braking force back through the shaft 55, the gears 29 and 25, the shaft 22, to the reel I5, effectively applying to the strand I9. If the tension in the strand should increase bea `predeterminegi tension yond the tension normally desired, the strand will y pull the sheave 55 toward the reel I8, causing movement of the nut 13 to the right (Fig. 1) to decrease the force of the screw 14 on the spring 49. through the tubular member 50, and thus decrease -the brakingforce of the brake elements 42 ald members 45 on the reel. The decrease in the force of the spring 49 will decrease the frictional force between the brake members and brake elements to thus decrease the braking force on the reelallowing the strand to more freely rotate the reel until the tension on the strand has been reduced to Vthaifnormally desired. During normal operation of the apparatus the tension in the strand creates a pull on the spring 5| l,to maintain the normal selected force in the spring` 49 and thus the normal braking force on the reel.;`

aavaioa i If, however, the tension in the strandshould decrease from that normally desired the spring Il will be free te apply additional force to the spring 48 through the connectingmeans o! the two springs, resulting in added braking force to the reel, even to stopping the reel if, for example,.

mal to the axis of the reel, centrifugal force would tend to move the brake members and elements closer together with variations in the speed of the revolution of the reel, thus rendering the braking means ineiective to maintain a constant tension on the strand. Such effects of centrifugal force are removed. however. by positioning the brake members and elements on an axis of a shaft normal to the axis of the reel, where of course if will not interfere with their functions. Furthermore, the brake elements and members lie in planes at right angles to the axisl of revolution unaiected by centrifugal force created by the revolution of the reel. K

Attention is also directed to the mechanism interposed between the strand and the brake i, mechanism, namely the support or carriage 58,'

the arms 5l and the lever 61 which are also unaffected by centrifugal force. If the conventional tension armV of the pivotal type should be employed it is apparent that the result of centrifugal force thereon during the rotation of the apparatus about the shaft Il would make it impossible to maintain a uniform tension on the strand. However, in the present structure the centrifugal force affecting the support 58 is consumed by the rolls 59, the latter permitting free movement oi the carriage with light strand tension despite the high relative speeds.

The embodiment ofthe invention herein disclosed .is merely rillustrative and may be widely modified and departed from in many ways without departing from the spirit and scope of the invention as pointed out in and limited solely by the appended claims.

What is claimed is:

i. A tension control apparatus ior a strand being withdrawn from a supply reel rotated about its axis by the withdrawal ci the strand and revolved about an axis normal to the rcel axis, a brake element operatively connected to the reel for rotation thereby about an axis disposed at right angles to the reel axis, a brake member held against rotation with the brake element and cooperating therewith to apply a braking force to the reel to create a given tension in the strand,

`and means controlled by the strand to acct the brake element and member to vary the braking force with variations in the tension of the strand.

2. A tension control apparatus for a strand being withdrawn from a supply reel rotated about its axis by the withdrawal oi' the strand and revolved about an axis normal to the reel axis, a brake element operatively connected to the reel for rotation thereby about an axis disposed at right angles to the reel axis, a brake member held against rotation with the brake' element, force applying means to cause relative movement of the element and member to apply a predetermined braking force to the reel and establish a .predetermined tension in 'the strand, and means controlled by the strand to ailect the force applying means to vary the said braking force with variations in the tension of the stran 3. A tension control apparatus for a strand being withdrawn from a supply reel rotated'about its axis by the withdrawal of the strand and revolved about anaxisnormal to the reel axis, a brake element' and a cooperating brake member lying in planes at right angles t0 the axis about which the reel revolves. force applying means to cause relative movement of the element and member to apply a predetermined braking force to the reel and establish a predetermined tension in the strand, and means controlled by the strand to aiect thel force applying means to vary the said braking force with variations in the tension of the strand.

4..A tension control apparatus for a strand being withdrawn from a supply reel rotated about vary the force applying means to cause variation of the said given tension in the strand, and means controlled by the strand to affect the force applying means to vary the said braking force with variations in the tension of the strand.

5. A tension control apparatus for a strand being withdrawn from a supply reel rotated about its axis by the withdrawal of the strand and revolved about an axis normal to the reel axis, a sheave about which the strand travels on leaving the reel, a support for the sheave'movable by the strand during variations in the tension thereof, a brake element operatively connected to the reel for rotation thereby about an axis disposed at right angles to the reel axis, a brake member held against rotation with the brake element and cooperating therewith to apply a braking force to ,y loi-akin1T force with variations in the tension oi the strand.

6. A tension control apparatus for a strand being withdrawn from a supply reel rotated about its axis by the withdrawal oi the strand and revolved about an axis normal to the reci axis, a sheave about which the strand travels on leaving the reel, a support for the sheave movable by the strand during variations in the tension thereof, a brake element operatively connected to the reel for rotation thereby about an axis disposed at right angles to the reel axis, a brake member held against rotation with the brake element, a

spring to apply a given force to the brake ele-A ment and member to cause relativev movement thereof to apply a predetermined braking force to the reel and establish a predetermined tension in the strand, and means controlled by the support to vary the force ci the spring.

7. A tension control apparatus for a strand being withdrawn from a supply reel rotated about right angles to the reel axis, a brake memberheld against rotation with the brake element, a spring to apply a given force to the brake element and member to cause relative movement thereof to apply a predetermined braking force to the reel and estab`ish a predetermined tension in the strand, means controlled by the support to vary the force of the spring, and means to alter the variations in the force of the spring by the support.

8. A tension control apparatus for a strand being withdrawn from a supply reel rotated about its axis by the withdrawal of the strand and revolved about an axis normal to the reel axis, a shaft driven by the reel and disposed at right angles to the axis of the reel, a brake element driven with the shaft, a brake member held against rotation with the shaft, and means to cause relative axial movement of the brake element and member to cause application of a braking force through the shaft to the reel.

9. A tension control apparatus for a strand being withdrawn from a supplyreel rotated about its axis by the withdrawal cf the strand and revolved about an axis normal to the reel axis, a (shaft driven by the reel and disposed at right angles to the axis of the reel, a brake element driven with the shaft, a brake member held against rotation with the shaft, and a spring to apply a force to the brake element and member to cause relative axial movement thereof to cause application of a braking force through the shaft to the reelfl l0. A tension control apparatus for a strand being withdrawn from a supply reel rotated about its axis by the withdrawal of the strand and revolved about an axis normal tothe reel axis, a

shaft driven bythe reel and disposed at right angles to the axis of the reel, a brake element driven with the shaft, a brake member held l against rotation with' the shaft, a spring to apply a force to the brake element and member to cause relative axial movement thereof to cause application of a braking force through the shaft to the reel, and means disposed concentric with the shaft to cause variations in the force of the spring.

' 1K1. YA tension control apparatus for a strand being withdrawn from a supply reel rotated about its axis by the withdrawal of the strand and revolved about an axis normal to the reel axis, a sheave about which the strand travels on leaving the reel. a support for the sheave movable by the strand during variations in the tension thereof, a shaft driven by the' reel and disposed at right angles to the axis of the reel, a brake element driven with the shaft, -a brake member held against rotation with the shaft, and means actuated by the support to cause the brake element and member to apply a braking force to the reel variable with variations in the tension of the strand,

12. A tension control apparatus for a strand being withdrawn from a supply reel rotated about its axis by the Withdrawal of the strand and revolved about an axis normal to the reel axis, a sheave about which the strand travels on leaving the reel, a support for the sheave movable by the strand during variationsl in the tension thereof, a

shaft driven by the reel and disposed at right angles to the axis of the reel, a brake element driven with the shaft, a brake member held against rotation with the shaft, a spring to apply a force to the brake element and member to cause relative axial movement thereof to cause application of a braking force through the shaft to the reel, and means controlled by the support to vary the said spring and braking forces.

GEORGE E. HENNING. JULIUS A. WAGNER. 

